Unistar Computers makes and sells a unique computer that is designed for a specific market. Cost information relating to that product is shown below:

$\backslash$table$[[$Sales price,$$3,100$ per unit$],[$Variable costs,$$2,600$ per unit$],[$Fixed costs,$$200,000$ total$]]$

Unistar expects to make and sell $620$ computers. Based on this information, the margin of safety expressed in units is:

Multiple Choice

$620$ units.

$400$ units.

$200$ units.

$220$ units.